بررسي رفتار پليمرهاي حافظه شكلي پاسخگو به حرارت

Investigation of Thermal-responsive Shape Memory Polymers Behavior

ﭘﻠﯿﻤﺮﻫﺎي ﺣﺎﻓﻈﻪ ﺷﮑﻠﯽ دﺳﺘﻪاي از ﻣﻮاد ﻫﻮﺷﻤﻨﺪ ﻫﺴﺘﻨﺪ ﮐﻪ ﺑﻪ ﻫﻨﮕﺎم ﻗﺮارﮔﯿﺮي در ﻣﻌﺮض ﻣﺤﺮك ﻫﺎي ﺧﺎرﺟﯽ ﺷﺎﻣﻞ دﻣﺎ، ﻣﯿﺪان ﻣﻐﻨﺎﻃﯿﺴﯽ، ﻧﻮر و ﻣﯿﺪان اﻟﮑﺘﺮﯾﮑﯽ ﻣﯽﺗﻮاﻧﻨﺪ ﺷﮑﻞ اوﻟﯿﻪي ﺧﻮد را ﺑﺎزﯾﺎﺑﯽ ﮐﻨﻨﺪ. ﯾﮑﯽ از ﭘﺮﮐﺎرﺑﺮدﺗﺮﯾﻦ دﺳﺘﻪ از اﯾﻦ ﭘﻠﯿﻤﺮﻫﺎ، ﭘﻠﯿﻤﺮﻫﺎي ﺣﺎﻓﻈﻪ ﺷﮑﻠﯽ ﭘﺎﺳﺨﮕﻮ ﺑﻪ ﺣﺮارت ﻫﺴﺘﻨﺪ. اﯾﻦ ﭘﻠﯿﻤﺮﻫﺎ داراي ﻣﺰاﯾﺎﯾﯽ ازﺟﻤﻠﻪ درﺻﺪ ﺑﺎﻻي ﺑﺎزﯾﺎﺑﯽ ﺷﮑﻠﯽ و ﻫﺰﯾﻨﻪي ﺗﻮﻟﯿﺪ ﭘﺎﯾﯿﻦ ﻣﯽﺑﺎﺷﻨﺪ و ﺑﻪﮐﺎرﮔﯿﺮي آنﻫﺎ ﻣﻨﺠﺮ ﺑﻪ ﮐﺎﻫﺶ ﺳﺎزوﮐﺎرﻫﺎي ﭘﯿﭽﯿﺪه و ﺑﻪ ﺗﺒﻊ آن، ﮐﺎﻫﺶ وزن و ﺣﺠﻢ ﺳﯿﺴﺘﻢ ﻫﺎ ﻣﯽﺷﻮد. ﭘﻠﯿﻤﺮﻫﺎي ﺣﺎﻓﻈﻪ ﺷﮑﻠﯽ ﭘﺎﺳﺨﮕﻮ ﺑﻪ ﺣﺮارت در زﻣﯿﻨﻪ ﻫﺎي ﻣﺘﻌﺪدي ازﺟﻤﻠﻪ ﭘﺰﺷﮑﯽ، رﺑﺎﺗﯿﮏ، ﻣﮑﺎﻧﯿﮏ و ﻫﻮاﻓﻀﺎ ﮐﺎرﺑﺮد داﺷﺘﻪ و ﻣﻨﺠﺮ ﺑﻪ ﺗﺤﻮﻻت ﻋﻈﯿﻤﯽ ﺷﺪه اﻧﺪ. ﻫﺪف از اراﺋﻪ اﯾﻦ ﻣﻘﺎﻟﻪ ﺑﺮرﺳﯽ رﻓﺘﺎر ﭘﻠﯿﻤﺮﻫﺎي ﺣﺎﻓﻈﻪ ﺷﮑﻠﯽ ﭘﺎﺳﺨﮕﻮ ﺑﻪ ﺣﺮارت و ﮐﺎرﺑﺮدﻫﺎي ﻣﺨﺘﻠﻒ آنﻫﺎ اﺳﺖ. در واﻗﻊ ﺑﺎ ﺑﺮرﺳﯽ ﭼﺮﺧﻪ ﺣﺮارت - ﻣﮑﺎﻧﯿﮑﯽ، ﻣﺪلﻫﺎي ﺳﺎﺧﺘﺎري، اﻧﻮاع ﻣﺨﺘﻠﻒ اﺛﺮ ﺣﺎﻓﻈﻪ ﺷﮑﻠﯽ، ﮐﺎرﺑﺮدﻫﺎي ﻣﺨﺘﻠﻒ، آﯾﻨﺪه و ﭼﺎﻟﺶﻫﺎي اﯾﻦ ﭘﻠﯿﻤﺮﻫﺎ ازﺟﻤﻠﻪ ﻧﯿﺮوي ﺑﺎزﯾﺎﺑﯽ ﮐﻢ و اراﺋﻪ راﻫﮑﺎر آن و ﺗﻬﯿﻪ ﺟﺪاول ﻣﺨﺘﻠﻒ از ﺗﺤﻘﯿﻘﺎت اﺧﯿﺮ ﺳﻌﯽ ﺷﺪه اﺳﺖ اﯾﻦ ﻣﻮاد ﺑﻪﻃﻮر ﺟﺎﻣﻊ ﺑﺮرﺳﯽ ﺷﻮﻧﺪ. ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ وﯾﮋﮔﯽﻫﺎي ﻣﻨﺤﺼﺮ ﺑﻪ ﻓﺮد اﯾﻦ ﭘﻠﯿﻤﺮﻫﺎ و ﺗﻼش ﺑﺮاي رﻓﻊ ﻣﺤﺪودﯾﺖ ﻫﺎي آنﻫﺎ، در آﯾﻨﺪه ﺟﺎﯾﮕﺰﯾﻦ ﺑﺴﯿﺎري از ﻋﻤﻠﮕﺮﻫﺎي ﻣﮑﺎﻧﯿﮑﯽ ﺧﻮدﻣﻮﻧﺘﺎژ ﺷﻮﻧﺪه ﺧﻮاﻫﻨﺪ ﺷﺪ.

Shape memory polymers are a type of smart materials that can recover their original shape when exposed to external stimuli including temperature, magnetic field, light, and electric field. One of the most widely used of these polymers is thermalresponsive shape memory polymers. These polymers have advantages such as a high percentage of shape recovery and low cost and using them results in reducing complex mechanisms that lead to reducing the weight and volume of the systems. Thermalresponsive shape memory polymers have been used in many fields, including medicine, robotics, mechanics, and aerospace and have led to great changes. This paper aims to study thermal-responsive shape memory polymers behavior and their different applications. In fact, by investigating the thermomechanical cycle, constitutive models, different kinds of shape memory effect, different applications, their future, and challenges of these polymers including low recovery force and its solution and preparation of various tables from recent researches, these materials have been comprehensively studied. Due to the unique properties of these polymers and the effort to overcome their limitations, they will become a candidate for many self-assembled mechanical actuators in the future.